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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 68-71页

作者：陈再良 college of Mechanical and Electrical engineering Soochow University Suz hou 215021 China

The bubble deformation processes were reported when gas was injected into polyme r melt flow field in another paper, the experiments showed that the deformation was severely affected by the volume of the bubble, and in turn, for the different bubbles, several different deformation processes were presented d uring their movement along the flow channel. In addition, we could find that the magnitude of the bubble volume was dependent upon the pressure difference of th e gas injection pressure and the melt pressure. In this paper, more experimental conditions were changed to investigate the parameters relevant to the detachmen t of bubbles from the injection nozzle. The experimental results show that the p ressure difference, the melt flow velocity as well as the melt pressure were all critical for the parameters, such as the bubble detachment time, the maximum bu bble diameters and the magnitude of the bubble volume. The morphology changes of bubble were very large when the flow field was abruptly changed, and the situat ions were more complicated.

关键词： bubble morphology detachment time geometry parameters flow field

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Plasma Spray Forming

厦门大学学报（自然科学版） 2002年第S1期41卷 33-34页

作者： FANG Jian-cheng 1, XU Wen-ji 2, SHI Yu-ying 1 (1.college of Mechanical engineering and automation, HQU, Quanzhou 362011, china 2.School of Mechanical engineering, DUT, Dalian 116023, china)

In the course of plasma spray, the plasma jet is comprehensively functioned by such effects as thermal pinch, magnetic pinch and mechanical compression and the flow is jetting at a high speed, the energy is concentrated and its center temperature is so high as to reach upwards of 15.000 ℃ which is capable of melting various kinds of materials inclusive of ceramic, it has a broad applied prospects in the fields of automobile, electronics, telecommunications, medical treatment, air navigation & space navigation and light industries etc because of being able to rapid fabricate thin-walled metals, ceramics and alloy parts thereof, metal moulds, functionally gradient material moulds and so on, and it has become a research spotlight for the scholars. The technology of plasma spray forming (PSF) is introduced, and the two different kinds of technique presented in this paper are studied. Some typical links in the course of technical process is also analyzed, including original prototype fabrication and surface treatment, post-treatment of formed workpiece and demoulding methods. When spraying, it should select the appropriate making methods of prototype according to the dimensions, shapes and forming accuracy as required by the formed parts. At the same time, it should be paid to the characteristic of the material for the prototype. The main purpose of surface treatment of the prototype is to raise the quality of formed parts and ensure the integrity demoulding of the coating. The method of the prototype’s surface treatment is closely related to the demoulding method, which is mainly comprised of destructive demoulding, non-destructive demoulding and composite demoulding, and is key technology in PSF. In order to eliminate these intrinsic defects and improve its performance, the fabricated parts can be given the necessary post-treatment so as to further raise the mechanical strength and surface quality. There are many methods for the post-treatment such as chemical reinforc

关键词： plasma spray forming forming technique

A novel dynamic coherent eddy model and its application to LES of a turbulent jet with free surface

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1671-1680页

作者： LU Jun,TANG HongWu,WANG LingLing & PENG Feng college of water conservancy of hydro-power engineering,Hohai University,nanjing 210098,china 1. college of water conservancy of hydro-power engineering Hohai University Nanjing 210098 China

We has developed a novel dynamic coherent eddy model,in which the coherent structure-Q criterion introduced by Hunt et al(1988)-is taken into account in the subgrid-scale turbulent viscosity based on the eddy viscosity *** proposed method is to combine the resolved-scale velocity-gradient tensor in the classical Smagorinsky model with Q criterion weighted.A kind of dynamic procedure which was averaged in a general process at temporal direction based on the autocorrelations of the characteristic resolved scales of turbulence was taken for the coefficient of subgrid *** model is implemented in the σ-coordinate and the filtered Navier-Stokes equations are solved by the operator splitting *** validation was explored to 2-D turbulent slot jet both in ambient environment and in regular *** prediction of the present model was compared with the experiment data,including the averaged velocity profiles,the velocity fluctuations and the Reynolds *** model performance is shown to be satisfactory.

关键词： LES subgrid-scale modeling σ-coordinate turbulent jet

Lagrangian formulation of continuum with internal long-range interactions

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Theoretical & Applied Mechanics Letters 2011年第4期1卷 60-63页

作者： Zaixing Huang a) college of Aerospace engineering,nanjing University of Aeronautics and Astronautics,nanjing 210016,{5. college of Aerospace engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Based on a new definition of nonlocal variable,this paper establishes the Lagrangian formulation for continuum with internal long-range *** from the existing theories,the nonlocal term in the Lagrangian formulation automatically satisfies the zero mean condition determined by the action and reaction *** this formulation,elastic wave in a rod with the internal long-range interactions is *** dispersion of the elastic wave is predicted.

关键词： nonlocal mechanics Lagrangian formulation long-range interactions physically-based nonlocal model

Heterogeneous reaction of NO_2 with sea salt particles

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Science china Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering,Peking University,Beijing 100871,china 2 college of Atmospheric Physics,nanjing University of Information Science and Technology,nanjing 210044,china 1. State Key Joint Laboratory of Environmental Simulation and Pollution Control college of Environmental Sciences and engineering Peking University Beijing 100871 China2. College of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing 210044 China

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.5. ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015.mol/*** results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

RESEARCH FOR CLUSTERING OF FEATURE MANUFACTURING-ORIENTED

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Chinese Journal of Mechanical engineering 2002年第1期15卷 11-14页

作者： Liu Xuan Shen Xiaohong Nie Xuejun Chen Shan college of Mechanical engineering and automation， Beijing University of Industry and Commerce，Beijing 100037，china college of Mechanical engineering and automation Beijing University of Industry and Commerce 北京 100037

The following questions are discussed: feature cluster, feature clusterconcept and the reasoning formula. The defect based on approach direction and feed direction areanalyzed. Feature tool axis direction concept and ... 详细信息

关键词： Feature Clustering of feature Tool axis direction

NMR Research on Cement Clinker and Its Structures in Early Age Hydration

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Journal of Wuhan University of Technology(Materials Science) 2011年第5期26卷 972-977页

作者：王晓钧 college of Materials Science and engineering Nanjing University of Technology

Clinker has long been regarded as a critical factor for cement hydration and solidification.α-C2S and β-C2S in 2CaO·SiO2（C2S） phase and C3S Monoclinic 1（C3S M1） and C3S Monoclinic 3 （C3S M3） in 3CaO·SiO2 （C3S） phase were clearly recorded in the 29Si MAS NMR *** content of C3S phase in the clinker deduced from the fine peak analysis coincides with the phase quantification analysis calculated by the Taylor-Bogue method based on XRF,which also accords to the statistical data in industrial *** provides a proof that C3S M1 and β-C2S phases have a prior reaction in the early age hydration of clinker,and demonstrates that aluminum coordination changes from tetracoordinated 4CaO·Al2O3·Fe2O3（C4AF） to hexacoordinated [Ca2Al（OH）6]（SO4）0.3·3H2O（Aft） in one day hydration and changes to the 3CaO·Al2O3·CaSO4·nH2O （Afm） in a seven-day hydration.

关键词： NMR clinker cement hydration

Encapsulation of inorganic particles by dispersion polymerization through ultrasonic irradiation

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Science china Chemistry 2005年第6期48卷 545-552页

作者： ZHANG Kai1,2, FU Qiang1, HUANG Yuhong2 & ZHOU Dehui2 1. college of Polymer Science and engineering, Sichuan University, Chengdu 610065. china 2. Institute of Structure Mechanics, china Academy of engineering Physics, Mianyang 621900, china 1. college of Polymer Science and engineering Sichuan University 610065 Chengdu China 2. Institute of Structure Mechanics China Academy of Engineering Physics 621900 Mianyang China

The nano-silica/polystyrene composite particles were prepared and characterized according to the following steps. First, the nano-silica particles were pretreated with surfactants under ultrasonic field. Second, the dispersion polymerization of styrene in a water/ethanol (1/6, weight ratio) medium, with poly(N-vinyl pyrrolidone) (PVP) as stabilizer and 2,2’-azobisizobu- tyronitrile (AIBN) as initiator in the presence of nano-silica particles was initiated with N2 purging through ultrasonic irradiation by taking its advantages of multieffect, i.e. dispersion, crushing, activation, and initiation. Finally, the polymerization kinetics characteristics were studied, and the encapsulation of composite particles was investigated with optical microscope, SEM, TEM, FTIR, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

关键词： composite particle, dispersion polymerization, ultrasonic irradiation.

Effects of Bahia Grass Cover and Mulch on Runoff and Sediment Yield of Sloping Red Soil in Southern china

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Pedosphere 2011年第2期21卷 238-243页

作者： LI Xin-Hu ZHANG Zhan-Yu YANG Jie ZHANG Guo-Hua WANG Bin college of Water Conservancy and Hydropower engineering Hohai University Nanjing 210098 (China) Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil Hohai University Nanjing 210098 (China) Jiangxi Institute of Soil and Water Conservation Nanchan9 330029 (China) china Irrigation and Drainage Development Center Beijing 100054 (China) college of Water Conservancy and Building engineering Northeast Agricultural University Harbin 150030 (China)

Rainfall,runoff (surface runoff,interflow and groundwater runoff) and soil loss from 5.m × 15.m plots were recorded for 5.years (2001-2005. in an experiment with three treatments (cover,mulch and bare ground) on sloping red soil in southern *** runoff and erosion from the Bahia grass (Paspalum notatum Flugge) cover plot (A) and mulch plot (B) during the 5.years were low,despite the occurrence of potentially erosive *** contrast,the bare plot (C) had both the highest surface runoff coefficient and the highest sediment *** were significant differences in interflow and surface runoff and no significant difference in groundwater runoff among *** runoff coefficients and duration of interflow and groundwater runoff were in the order plot B > plot A > plot *** of Bahia grass cover were excellent,indicating that the use of Bahia grass cover can be a simple and feasible practice for soil and water conservation on sloping red soil in the region.

关键词： groundwater runoff interflow lysimeter soil properties surface runoff